1) Field of the Invention
The instant invention refers to phototherapy equipment, particularly for the treatment of hyperbilirubinemia, designed to deliver excellent performance and high operational flexibility and safety due to its unique construction, consisting of a small number of blue-spectral-high-radiation light emission diodes (LED's), with advanced microprocessing and communication capacity with other equipment, everything in reduced sized and easily handled.
2) Description of Related Art
Phototherapy is normally used in the treatment of neonatal hyperbilirubinemia, being the patient exposed to radiation focused on the visible light blue spectrum for a time to be determined according to the healthcare professional in charge.
Hyperbilirubinemia is a syndrome that affects a lot of newborns, corresponding to the incapacity of the infant of metabolizing and eliminating the bilirubin pigment from its blood stream accordingly. At high doses in the blood, bilirubinemia makes the infant to present yellowish color of the skin and, in the most critical events, it can generate neuromuscular and cognitive development impairment in the infant.
The newborns phototherapy treatment significantly reduces the levels of bilirubin. Basically, the light emitted by the phototherapy equipment enables to transform bilirubin into other substances more easily eliminated by the body through photo-oxidation, configurational isomerization, and structural isomerization.
The introduction of phototherapy in the treatment of neonatal bilirubinemia since its advent in the late 1950's and later by virtue of the great evolution in the types of the lamps used, has minimized the risks, without, however, eliminating the adverse side effects of the ultraviolet rays and infrared rays on the patient's body. This occurs because the conventional light sources (lamps) not only generate it in the efficient spectrum for the treatment, but also emits infrared and ultraviolet rays that are harmful to the patient's body.
With the advance of the electronic technology in the illumination field, we now have components that help engineering in developing better, more efficient and safer medical equipment, mainly when it comes to saving human lives. The use of different types of lamp in the treatment of newborns is world-widely used, and the benefits of this treatment are unquestionable.
The first phototherapy apparatus used fluorescent lamps, which produced a more efficient phototherapeutic effect than the irradiation of light by means of ordinary lamps, since they emit a high rate of “cold” luminous radiation, that is to say, a whiter light spectrum. However, the level of irradiation of fluorescent lamps was very low, and it was necessary to use a large number of lamps simultaneously, which would require the use of a large-size apparatus so that the radiating energy could be sufficient for the desired healing effect.
In order to overcome this serious drawback, one researched and studied the application of high-irradiance fluorescent blue lamps, developed and manufactured with the main purpose of being used on phototherapy apparatus. However, although these lamps emitted light with properties more suitable for the implementation of phototherapy, when compared to the ordinary incandescent lamps, they still had the outstanding disadvantage of exhibiting long wave length, occupying enormous spaces in the newborn Intensive therapy units in the hospitals.
With the advance of technology, halogen lamps were introduced into the market, which are lamps having filament enclosed in a halogen gas atmosphere that have a performance very superior to that of fluorescent lamps (notwithstanding the higher power consumption) in the treatment of hyperbilirubinemia, with a quite reduced size. This type of lamp, however, produces much heat and has a relatively short useful life (about 2,000 hours), and should be replaced at intervals shorter than desirable.
As a consequence, phototherapy equipment that operates with halogen lamps should have some kind of refrigeration system, by means of fans, and infrared and ultraviolet rays filters, in order to reduce the undesirable effects to the newborn's body.
In order to eliminate the excess heat caused by the phototherapeutic luminous irradiation with halogen lamps, the technology evolved to the application of solid state lamps or ordinary blue LED's (light emission diodes). The LED's are capable of generating a lot of luminosity despite their size and they do not heat much, which is a surprise when compared to the luminosity they generate.
However, due to their reduced size, the conventional LED's do not have good irradiation if considered unitarily. In order to obtain a satisfactory treatment effect, many LED's should be used in conjunction and the equipment should be placed very close to the patient's body.
LED's phototherapy equipment is, therefore, limited to some applications where it is necessary to position the source of light very near to the patient.
A landmark in the use of LED's for the treatment of hyperbilirubinemia is the article of the American journal “Pediatric Research” of November, 1998 (volume 44, number 5), which provides on the use of LED's in the treatment of hyperbilirubinemia and suggests the use of two light sources of different wave lengths used simultaneously during the procedure. The method disclosed in this article predicts the combination of one hundred (100) LED's series combination (preferably three series) where the light overlay of the different wave lengths would enable a large amount of light radiation, which does not happen with the other kinds of conventional light sources tested. The great inconvenient of this treatment, however, is that in order to obtain the appropriate radiation for the hyperbilirubinemia treatment, it is necessary a very large amount of LED's (three hundred total). Therefore, the resulting equipment is considerably large and expensive, both in terms of manufacturing and operation (due to the need of installation and feed of the 300 LED's with electric power).
This first document of the prior art does not report details of the phototherapy equipment used, but only the first experience using LED's in the treatment of hyperbilirubinemia. Anyhow, it is worth noting that this scientific paper proved the viability and efficacy of the use of LED's, which led several manufacturers to develop phototherapy equipment with more developed and efficient LED's.
Notwithstanding, in 1997, U.S. Pat. No. 5,698,866, was granted to a phototherapy equipment having LED's for the production of luminosity, although the object of this patent is the use of lens and collimators to properly direct the light produced by the LED's. FIGS. 1 and 4 show that the operational area of the several LED's is limited, since they are positioned on the edge of a small hand piece. The equipment thereof was not idealized for the treatment of hyperbilirubinemia.
A second study on phototherapy with LED's, now published in the American journal specialized in the medical area, “The Journal of Pediatrics” (June/2000, volume 136 and number 6), shows an experience with 69 patients for the treatment of hyperbilirubinemia through a prototype phototherapy equipment (the photography of which can be seen in the article). The prototype equipment contains 6 sets with one hundred (100) blue LED's of gallium nitride each, which radiate the light as far as approximately 20 cm from the patient. Since this equipment comprehends a large amount of blue LED's (six hundred), it is intrinsically expensive, large (which limits its handling over the patient) and difficult to operate (high electric power consumption).
Another phototherapy equipment for the treatment of hyperbilirubinemia is disclosed on documents WO 2004/033028 and WO 2004/033029 and comprehends a plurality of LED's that emit light in the blue spectrum (efficient when transforming bilirubin) and, in addition, a few LED's that emit light in the yellow spectrum, with a view to eliminate the feelings of nausea caused by the LED's that emit blue light. As mentioned in the document, the equipment uses something like one thousand (1,000) LED's that emit light in the blue-green visible spectrum for the treatment of hyperbilirubinemia together with approximately three hundred and twenty (320) LED's emitting yellow light to minimize the discomforts caused by the blue light, that is, approximately one thousand, three hundred and twenty (1,320) LED's to radiate an appropriate amount of light for the treatment.
The drawbacks arising from the large number of LED's presented in the equipment are the high manufacturing and operational costs (high power consumption, high replacement cost of the over 1,300 LED's in the end of their useful life), and the significant dimensions, due to the large number of existent LED's, limiting the equipment positioning mobility regarding the newborn under treatment.
Another example of equipment used for the treatment of hyperbilirubinemia that has a plurality of conventional LED's is present in document WO 2004/032714. This equipment has a light diffusing panel that enhances the uniformity of exposure of the patient to light, by using a plurality of LED's arranged in series and in an non-uniform manner, and also has a directing mechanism that guarantees its positioning always in a correctly aligned manner over the patient, so that the incident light can be adequate.
However, like the equipment mentioned before, this one uses about seven hundred fifty (750) LED's that emit light in the visible blue-green spectrum for the treatment of hyperbilirubinemia, making it very expensive and with very large dimensions due to the great number of LED's that should be accommodated on the light diffusing panel. Evidently, the drawbacks of high manufacture and operational cost of this equipment also are significant.
Still, another phototherapy equipment for the treatment of hyperbilirubinemia is showed on document EP 1 138 349, and includes a plurality of LED's for the generation of luminosity, being that these LED's can be positioned in flexible structures that enable its placement around the patient's body.
Finally, another relevant prior art, of the same author of the article of the American journal “Pediatric Research” of November, 1998, is the North-American U.S. Pat. No. 6,596,016, which shows phototherapy equipment for the treatment of hyperbilirubinemia comprehending a flexible base to which are associated a plurality of LED's, which creates all inconvenient already mentioned for the other previously analyzed equipment.
Every equipment for the treatment of hyperbilirubinemia provided with the LED's currently available present some or all drawbacks of being large, heavy and very expensive, whether regarding the manufacture or the operation, which makes its handling close to the patient difficult, thus causing extremely high expenses for the hospitals and clinics that use them.